When a Furnace Refused to Light: A Knoxville Homeowner’s Success Story

At HEP, our team of experts in Knoxville offers top-notch Heating and Air Conditioning services. We’re proud to provide reliable Heating and Air Conditioning in Knoxville.

Customer Issue
A homeowner discovered that their downstairs heating unit, tucked away in the attic, simply wouldn’t turn on. There was no warm air coming through the vents, and resetting the thermostat had no effect.

Diagnosis and Findings

When our HEP technician arrived, they performed a systematic check of the furnace. All safety components—the inducer motor, flame sensor, hot-surface igniter and blower motor—were in good shape but weren’t getting gas flow. This pointed to a faulty gas control valve as the likely culprit.

Installing the Right Replacement

Our HEP technician removed the old valve and installed a brand-new one that matched the unit’s specifications. All gas line fittings were carefully resealed and tested with specialized equipment to guarantee there were no leaks.

Above: The data label on a Goodman furnace provides critical model and serial number details, helping technicians order the exact replacement parts.

Verifying Electrical Signals

With the new valve in place, the next step was to confirm that the ignition circuit and safety switches were receiving proper power. Our technician used precise readings to ensure voltage and current were within manufacturer guidelines before proceeding.

Checking Safety Components

Modern furnaces include a pressure switch to prevent operation if airflow is obstructed. Our HEP technician confirmed this switch and its wiring were functioning correctly, giving us confidence to move on to the final fire-up.

Final Fire-Up and Testing

All set, our HEP technician ignited the furnace. A clean flame appeared, and within minutes warm air began circulating throughout the home—just as intended.

Key Takeaways for Homeowners

• Record Your Equipment Details: A quick photo of your furnace’s data label can save time when ordering parts.
• Rely on Certified Pros: Proper installation and sealing of gas connections are vital for safety and efficiency.
• Keep Up with Annual Maintenance: Small issues—like a worn valve—are easier (and cheaper) to fix before winter arrives.
• Know the Warning Signs: If your furnace won’t ignite, or you detect unusual smells, call a qualified technician rather than attempting a DIY fix.

This gas valve replacement was performed by a HEP technician in Knoxville, restoring dependable warmth and peace of mind to the homeowner. If your heating system ever leaves you in the cold, we’re ready to help.

Published on November 20, 2025